Title

Corrosion rate of a penny

Problem Scenario

Broad Question

Which type of soda can corrode a penny the most?

Specific Question

Do different types of soda affect the corrosion rate of a penny?

Hypothesis

It is hypothesized that the Coca-Cola will have the highest corrosion rate.

Graph of Hypothesis

Variables

Independent Variable:

Corrosion rate

Dependent Variable:

The soda type

Variables That Need To Be Controlled:

Amount of soda

Vocabulary List That Needs Explanation

Corrosion - When something is broken down, or torn away.

---

---

---

---

General Plan

In this experiment I will measure a certain amount of soda in 4 different glass cups. After that I will measure the mass of the penny, then drop a regular copper penny into each of the cups. I will keep the pennies in the cups for two weeks, and measure the mass when the time limit is up. I will compare the masses to see if there was any corrosion of the pennies.

Potential Problems And Solutions

If the cup tips over during the experiment.

Safety Or Environmental Concerns

Do not drink the soda, or eat the pennies.

Experimental Design

Controlled, manipulated experiment

Number Of Trials: 1

Number Of Subjects In Each trial: 4

When data will be collected

Two weeks after the pennies are inserted

Number of Observations:

4

Where will data be collected?: My house

Resources and Budget Table

Data Table

Time Line

• February- Begin designing experiment
• March - Finish designing experiment/ Perform experiment
• April - Perform Experiment and analyze data

---

---

---

---

Background Research

Diet soda is the same as regular soda but it uses a different type of sweetener in the ingredients. In the regular soda drinks, it is sweetened using natural sugar. With diet, the sugar has been changed and been replaced with a different type of artificial sweetener, which is what gives the beverage less calories. Studies today show that the sweetener does not make the drink any healthier and it is proved that it does not help anyone lose weight.
Like all materials made from copper, pennies are able to corrode. Though copper is resistant to most types of materials, it tends to corrode when exposed to oxygen, sulfur or ammonia. The copper reacts with oxygen molecules in a process known as oxidation. After oxidation has taken place, the byproduct of this reaction leaves a layer of green film on the surface of the penny. This green film is sometimes called patina.

Reference

Lacoma, Tyler. "Why Do Pennies Corrode?" EHow. Demand Media, 28 June 2009. Web. 02

"Difference Between Diet Soda and Regular Soda | Difference Between | Diet Soda vs Regular Soda." Difference Between Similar Terms and Objects. Web. 05 Apr. 2012.

Beach, Emily. "Why Do Pennies Change Color?" EHow. Demand Media, 10 July 2009. Web. 01 May 2012. <http://www.ehow.com/how-does_5169366_do-pennies-change-color_.html>.

Detailed Procedure

First, I will take four brand name sodas (Coke, Pepsi, Diet Pepsi, Diet Coke) and pour a small amount into four glass cups. Before the pennies are inserted, the mass of each penny will be measured. I will mark the pennies, and cups to tell which penny goes with which cup. After the masses have been recorded, I will drop one penny in the cups. They will sit there for approximately 1-2 weeks. Once the time limit is up, I will take all the pennies out and measure the mass again to see if the soda had corroded the penny in any way.

Diagram

Photo List

---

---

---

---

---

Results

All Raw Data

Graphs

Photos

---

---

---

---

---

Data Analysis

Conclusion

The conclusion to this experiment is that there was very small change in the mass. My hypothesis for Coke soda being the soda that corroded the penny the most turned out to be true, but slightly. The total change in mass was very small, and I think that if I wanted to actually test farther into this experiment to see how much the Coke could corrode the penny, I would need to let it sit for a much longer time.

Discussion

In this experiment, the data typically did not show that much of a pattern. The mass only changed about 1 to 3 grams for every penny, which is the only trend that was found. The relationship between the independent and dependent variable is somewhat strong. The soda type stayed the same, and did have an effect on the corrosion rate of the penny, but it was not a large one. The relationship wasn't very strong because the soda did not change the mass of the penny by very much. I was able to answer the experiment question which was: Do different types of soda effect the corrosion rate of a penny? I used diet and non diet soda to see if the diet had a less corrosion rate. The regular soda, did have a slightly higher corrosion rate, but only by 1 or 2 grams. The experiment did not have any problems while it was being performed. The data also did not have any errors, because I measured the mass at least 2 times to double check my answers. There isn't a lot that can be done to help others use this data. If you wanted to, you could perform the experiment on your own to test if a certain type of soda is worse for you. For understanding or solving a problem, you can take different brand name sodas to see if that has an effect on the corrosion rate of a penny, or other common objects that can be corroded. In the real world, scientists can use this information to, again, test which soda is worse for you. It could be useful to some people to know which soda is worse because mom's or dad's would probably like to know which sodas to not give their children. This experiment could be advanced in many ways. I could leave the penny in for a longer period of time to get better results. I could also use different brand name sodas, ( Mountain Dew, Sunkist, Sprite, etc) to test which one has the highest corrosion rate. I do not necessarily have to use a penny to test the corrosion rate, I could use another object. The results overall do not give much of a benefit to the society of science.

Benefit to community/Science

This experiment did not have a large benefit to the community because it doesn't have anything to do with the ecosystem or things that affect the outside world.

Abstract

Does soda type affect the corrosion of pennies? It was hypothesized that Coke would have the highest corrosion rate out of the four brand name sodas that I tested. Before the experiment you should probably look up the background of corrosion and the effects of diet and non diet soda.
Diet soda is the same as regular soda, except it uses a different type of sweetener that makes the beverage have less calories. It has been scientifically proven that diet soda does not help a person lose weight. All materials that are made from copper, are able to corrode. Copper is usually resistant to most materials, but it tends to corrode when exposed to oxygen, sulfur, and ammonia. The copper reacts with oxygen molecules in a process called oxidation. After oxidation has taken place, the byproduct of this reaction leaves a layer of green film on the surface of the penny. This green film is sometimes called patina.
In this experiment there wasn't many steps that needed to be followed when it came to performing and setting it up. First, I would measure the mass of four regular copper pennies, and mark them to know which one is which. Then, I would put Coke, Diet Coke, Pepsi, and Diet Pepsi inside four glass cups. The proper penny went in the appropriate cup, and I let them sit for 2 weeks. After the pennies had been inside the cups, I took them out and measured the mass again. I compared the before and after masses to see if there was any corrosion involved. The masses were measured in grams. After the data was collected, I was quite disappointed with the results.
When I looked at the results for the experiment, it wasn't what I expected. My hypothesis did turn out to be correct, but only by 1 gram. Diet Coke had the second highest corrosion rate. I think the thing that impacted the corrosion rate the most in this experiment was the brand of soda. The Coke product had a slightly higher rate than Pepsi.
Although this experiment is good knowledge to have, it does not have a strong effect on the scientific community.

---

Like all materials made from copper, pennies are subject to corrosion. Though copper is resistant to most types of materials, it tends to corrode when exposed to oxygen, sulfur or ammonia. This means that a penny will corrode when simply exposed to oxygen in the air we breathe every day. The copper reacts with oxygen molecules in a process known as oxidation. After oxidation has taken place, the byproduct of this reaction leaves a layer of green film on the surface of the penny. This green film is sometimes called patina and is considered a desirable effect when it develops on certain other copper products. The scientific term for this green layer of corrosion is copper-hydroxide-carbonate.
Read more: Why Do Pennies Change Color? | eHow.com http://www.ehow.com/how-does_5169366_do-pennies-change-color_.html#ixzz1tcUlIbot